Circular Measure

01 • Degrees → radians formula
01 Degrees → radians formula
02 • Arc length s = rθ
02 Arc length s = rθ
03 • Sector area A = ½ r²θ
03 Sector area A = ½ r²θ
04 • Sine rule
04 Sine rule
05 • Cosine rule & rearrangements
05 Cosine rule & rearrangements
06 • Area of triangle using sine
06 Area of triangle using sine
07 • Example: find radius from arc length
07 Example: find radius from arc length
08 • Concentric arcs: ratio & perimeter
08 Concentric arcs: ratio & perimeter
09 • Segment perimeter (chord + arc)
09 Segment perimeter (chord + arc)
10 • Concentric arcs with PS ⟂ OR
10 Concentric arcs with PS ⟂ OR
11 • Minor arc length from sector area
11 Minor arc length from sector area
12 • Concentric circles: find OA & area ratio
12 Concentric circles: find OA & area ratio
13 • Segment area from θ and arc length
13 Segment area from θ and arc length
14 • Inscribed sector (perpendicular) — θ, arc, area
14 Inscribed sector (perpendicular) — θ, arc, area
15 • Tangents P,Q meet at R — shaded area
15 Tangents P,Q meet at R — shaded area